100999-26-6Relevant articles and documents
Structure-Activity Relationships in the trans-Hexahydroindolophenanthridine ("Benzergoline") Series. 2. Resolution, Absolute configuration, and Dopaminergic Activity of the Selective D1 Agonist CY 208-243 and Its Implication for an "Extended Rotamer-Based Dopamine Receptor Mode
Seiler, Max P.,Floersheim, Philipp,Markstein, Rudolf,Widmer, Armin
, p. 977 - 984 (1993)
4,6,6a,7,8,12b-Hexahydroindolophenanthridines ("benzergolines") was the first structural class of potent and selective dopamine D1 agonists lacking a catechol group.In order to determine the enantioselectivity of the 7-methyl derivative in the adenylate cyclase assay, its 5,5a-dihydro precursor was resolved and both enantiomers oxidized to the final products.The biological activity was found to reside entirely in the (-)-enantiomer (-)-1 (CY 208-243).An X-ray study of its (-)-mandelic acid salt revealed a 6aR,12bR absolute configuration, which, in confirmation of the struct ure hypothesis, corresponds to that of the ergolines.Unexpectedly, an axial conformation of the N-methyl group was observed in the crystal structure.In contrast, subsequently analyzed crystals of the free base of (-)-1 revealed an equatorial conformation of the N-methyl group, which, we assume, represents the bioactive conformation.Based on the determined absolute configuration, (-)-1 could be oriented in a previously described "rotamer-based dopamine receptor model", which allowed the localization of a "subtype selectivity-inducing site" (aryl binding site at the D1 receptor, steric barrier at the D2 receptor), marked by the conformationally fixed "additional" phenyl group of the benzergoline molecule.
INDOLOPHENANTHRIDINES USEFUL AS DOPAMINERGIC AND ANALGESIC AGENTS
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, (2008/06/13)
4,6,6a,7,8,12b-hexahydro-indolo[4,3-ab]phenanthridines are useful as dopaminergic and analgesic agents.